<template>
  <el-container class="home-container">
    <!-- 头部区 -->
    <el-header>
      <div>
        <img src="../assets/heima.png" alt="" />
        <span>电商后台管理系统</span>
      </div>
      <el-button type="info" @click="logout">退出</el-button>
    </el-header>
    <!-- 页面主区 -->
    <el-container>
      <!-- 侧边栏 -->
      <el-aside :width="isCollapse ? '64px' : '200px'">
        <div class="toggle-button" @click="toggleCollapse">|||</div>
        <el-menu
          default-active="2" class="el-menu-vertical-demo"
          background-color="#333744" text-color="#fff"
          active-text-color="#409EFF" :unique-opened="true"
          :collapse="isCollapse" :collapse-transition="false"
          :router="true" :default-active="activePath"
        >
        <!-- 一级菜单 -->
          <el-submenu
          :index="item.id+'' " 
          v-for="item in menulist" 
          :key="item.id"
          >
            <template slot="title">
              <i :class="iconsObj[item.id]"></i>
              <span>{{item.authName}}</span>
            </template>
            <!-- 二级菜单 -->
            <el-menu-item 
            :index="'/'+ subItem.path+''" 
            v-for="subItem in item.children" 
            :key="subItem.id"
          @click="saveNavState('/' + subItem.path)"
              >
              <template slot="title">
                <i class="el-icon-menu"></i>
                <span>{{subItem.authName}}</span>
              </template>
            </el-menu-item>
          </el-submenu>
        </el-menu>
      </el-aside>
      <!-- 右侧内容 -->
      <el-main>
        <!-- welcome路由占位符 -->
        <router-view></router-view>
      </el-main>
    </el-container>
  </el-container>
</template>

<script>
export default {
  data(){
    return{
      menulist:[],//左侧菜单数组
      iconsObj:{
        '125': 'iconfont icon-users',
        '103': 'iconfont icon-tijikongjian',
        '101': 'iconfont icon-shangpin',
        '102': 'iconfont icon-danju',
        '145': 'iconfont icon-baobiao',
      },
      isCollapse:false,
      activePath: ''
    }
  },
  created() {//生命周期函数
    this.getMenuList()
    this.activePath = window.sessionStorage.getItem('activePath')
  },
  methods: {
    logout() {
      window.sessionStorage.clear();
      this.$router.push("/login");//清空token回到登录页  
    }, 
    async getMenuList() {//获取服务器左侧菜单数组
      const {data: res} = await this.$http.get('menus')
      if(res.meta.status !== 200) return this.$message.error(res.meta.msg)
      this.menulist = res.data
    },
    toggleCollapse() {//折叠展开左边菜单
    this.isCollapse = !this.isCollapse
    },
    saveNavState(activePath){
      window.sessionStorage.setItem('activePath',activePath)
      this.activePath = activePath
    }       
  }
};
</script>

<style lang="less" scoped>
.home-container {
  height: 100%;
}
.el-header {
  background-color: #373d41;
  display: flex;
  justify-content: space-between;
  padding-left: 0;
  align-items: center;
  color: #fff;
  font-size: 20px;
  > div {
    display: flex;
    align-items: center;
    span {
      margin-left: 15px;
    }
  }
}
.el-aside {
  background-color: #333744;
  .el-menu {
    border-right: none;//去除下拉菜单栏边框
  }
}
.el-main {
  background-color: #eaedf1;
}
.iconfont{
  margin-right: 10px;
}
.toggle-button{
  background-color: #4A5064;
  font-size: 10px;
  line-height: 24px;
  color: #eaedf1;
  text-align: center;//居中
  letter-spacing: 0.2em;
  cursor: pointer;//设置鼠标光标样式
}
</style>